Electromechanical lock devices that include an electrically co-acting or controlled latching mechanism for manoeuvring a lock cylinder are known to the art. For example, U.S. Pat. No. 5,839,307, the Swedish patent SE 9904771-4, and the European patent publication EP 1 134 335 A2 describe such lock devices. It is there described how an actuator is rotated by means of an electric motor. The actuator in turn permits or prevents the movement of a side bar.
In order to achieve greater flexibility it is preferred that the latching mechanism is entirely included in the cylinder core. In this way you can use the same lock cylinder housing as in all-mechanical lock devices. However, the problem is that the space in the cylinder core is limited and that the assembly of the latching mechanism can be difficult to realize in a simple way.
A known way to assemble a latching mechanism entirely provided in the core is to drill a hole in the inner end surface of the core, which extends in the longitudinal direction of the core. The drawback with this solution is that such a hole in the end surface limits the placement of other parts in the lock device, such as the coupling of a follower to the core.
It is also known to provide the latching mechanism in a recess in the barrel surface of the core, see for example the above mentioned European patent publication EP 1 134 335 A2. A drawback associated with this solution is that a cover must be provided, which keeps the actuator and the side bar in place. This leads to a weakening of the latching mechanism since the cover can yield when the core is subjected to large turning forces.